About the Lectin

The seeds of Datura stramonium, the thorn apple or jimson weed, contain a lectin which binds specifically to β(1,4)-linked oligomers of N-acetyl-D-glucosamine. The protein contains two equivalent binding sites for GlcNAc oligomers. Inhibition studies indicate that chitotriose is 6 times more potent than chitobiose, chitobiose is 90 times more potent than the monosaccharide, GlcNAc 1 . The extended binding site of DSA will accommodate repeating units of GlcNAc β(1,4) muramic acid 6 . Pneumococcus type 14 capsular polysaccharide 2 and carcinoembryonic antigen 3 both react strongly with the lectin. DSA will also react with N-acetyllactosamine, and the immobilized lectin has been used to purify poly-N-acetyllactosamine containing glycopeptides 4,7 . It is distinct among poly-N-acetyllactosamine-binding lectins in that it apparently does not require the presence of a GlcNAcβ(1-6)-linkage for interaction. 8 DSA specifically reacts with certain developing neural cells 9 , muscle fibers 10 , and a poorly differentiated hepatic carcinoma. 11 DSA rapidly stimulates histamine release from rat peritoneal mast cells 12 , and is also distinct among related solanaceous lectins of similar specificity in that it is mitogenic for human lymphocytes. 13 A possible fragment of DSA with a MW=32,000 contaminates most preparations. The lectin tends to form aggregates when lyophilized and when stored at high concentrations 5 . The aggregated lectin is a more potent mitogen for human peripheral blood lymphocytes than the non-aggregated form. The lectin is very stable when stored at 4°C, with no detectable loss in activity over several years. Most of the conjugated forms of the lectin are stable when frozen in aliquots, but it is recommended that all forms of DSA be stored refrigerated.

REFERENCES

  1. Crowley, J. F., et al. (1984). Arch. Biochem. Biophys. 231 : 524-533
  2. Lindberg, B., et al. (1977). Carbohydr. Res. 58 : 177-186
  3. Hammarstrom, S., et al. (1975). PNAS, USA.72 : 1528-1532
  4. Cummings, R. D. and Kornfeld, S. (1984). J. Biol. Chem. 259 : 6253-6260
  5. Crowley, J. F. and Goldstein, I. J. (1981). FEBS Lett. 130 : 149-152
  6. Desai, N.N., et al. (1981). Anal. Biochem. 197 : 345-353
  7. Yamashita, K., et.al. (1987). J. Biol. Chem. 262 : 1602-1607
  8. Kawashima, H., et al. (1990) Glycoconj. J. 7 : 323-334
  9. Griffith, C. M., et al. (1995) Teratology 52 : 286-297
  10. Kirkeby, S., et al. (1997) J. Muscle Res. Cell. Mot. 18 : 31-41
  11. Goulot-Chassaing, C. and Bourrillon, R. (1997) Eur. J. Biochem. 247 : 1091-1101
  12. Matsuda, K., et al. (1994) Jap. J. Pharmacol. 66 : 195-204
  13. McCurrach, P.M. and Kilpatrick, D.C. (1988) Scand. J. Immunol. 27: 31-34

Product Characteristics
Buffer 0.01M Phosphate – 0.15M NaCl, pH 7.2-7.4
Blood Group Nonspecific.
Activity 30 μg/ml will agglutinate human type O erythrocytes.
Inhibitory Carbohydrate Chitotriose > Chitobiose > N‑acetyl‑D‑glucosamine.
Molecular Weight Two subunits of MW=40,000 and 46,000 by SDS-PAGE.
Caution Avoid freezing the purified lectin. Store refrigerated at 5-8°C.